Lock stitch sewing machine and method of lubricating the same



July 29, 1947- G. SAUER 2,424,855

LOCK STITCH SEWING MACHINE AND METHOD OF LUBRICATING THE SAME Filed March 2.8, 1942 4 Sheets-Sheet l FiGi.

Q WM f GEORGE Ms BY Qn/ i? July 29, 1947. G. sAUER 2,424,355 LOCK STITCH SEWING MACHINE' AND METHOD OF LUBRICATAING THE SA-ME Filed' Maren 28, 1942 4 sheets-snaai 2v LNVENTOR.

G50/raf .SAI/En July 29, 1947.

G. sAuER LOCK STITCH SEWING MACHINE AND METHOD OF LUBRICATING THE SAME Filed March 28. 1942 4 Sheets-Sheet 3 INVENTOH. GEORGE 634050 m .vm

ATT

July 29, 1947. s. lsAuER .2,424,855

LOCK STITCH SEWING MACHINE AND METHOD 0F LUBRICATING THE SAME Fiied March 28, 1942 4 sheets-sheet 4 INVENTOH. GEORGE SAI/ER ATTO Patented July za 1947 2,424,855

UNITED i 2,424,855.

LOCK STITQH SEWING MACHINE AND MHQWQF "RICATING THE .SAME George Sauer, ihicaso 11.1.1-, .assigner to. Union Specie. Machin Cemnany, Chicago, lill a ser- .iieraiiie- Application March-28, 1942, Serial No. 436,554

v`1. Y 52 This invention relates to improvements in A special feature vofthe invention is the `proing machines and particularly lool:y stitohm `visionof positive means for ieeclingthe lubricant, Shines irl Which ltile stitch forming vdevices :in: in ,closely regulated amounts, f-romthe reservoir clude one or `I nore rotary hooks having their axes. Yto the hook raceway. YFor this purpose. vpositive vertically disposed. It relates also .to an im. a pumping means is preferably associated directly proved method of lubricating the raceWayhf-.a with the .hook shalt .and is operated, .upon rota- YOPLIY hOOk in. Such a machine. j tion of `the latter, in a Way to force .oil delivered A problem .has been presented, in connection to the interior of the shaft into the. hook race- With machines ofthe above-noted character, in way. To insure close regulation v ofthe lubricant the Way Vof eiecting proper lubrication .of the 1:9. and avoid an .over-abundant .supply of the same hook raceway. This racevvay, formed in the 130.- to, the .raceway, a readily controllable valve is tating member of the hook, cooperates with ya provided at kan appropriate point in Athe conrib 0n .the stationary .component or bobbin .case nectionbetween :the .reservoir and the interior of of the unit. At thev high speeds at which `it the. hook shaft. The lubricant is supplied to the desirable to operate machines of this character, 'Llihollow of the. shaft, lpreferably by gravity, in juSt in present-day practice, itis very important'that thenigihteamount yto provide adequate lubrication adequate lubrication be provided vfor the .hook without wastageoi the oil and danger ofsoiling raceway; otherwise the hook. andthe .associated the work. Moreover, .the construction as a whole parts Will quickly become overheated and .give isusuch .that vthis proper supply ofl the lubricant, rise to serious consequences, It should be ob.- 2,0v toV .meet .the requirements of the .hook racevvay, served in this connection, that lthehook makes. takes place regardless ,of thefheightr oi the o il in tivo revolutions for each cycle ofthe machine. the reservoir. On the other hand, too much lubrication isV also A further feature vof the invention is in the objectionable sinceany excesscil, whichmayacparticular construction .and arrangement of` the. cumulate in the racewayis likely. to be .thrown 25 lubricant-reservoir foreach of the rotary hooks. and spattered about bythe rapidlyirotating hoor;A This construction is such as .to provide a reserand thus soil the threads and the lmaterial :being ,voin ofv maximum capacity Within the available stitched. space and is also'. suchy as .to .provide automatic An object of theA present inventionhaszbeenfto.. lubrication of ycertain relatively moving parts in provide adequate, but not excessive, lubrication 39 addition to the hook raceway. Thus, provision is tor the Wearing surfaces of a rotatinghool, with madeV for the. lubrication of certain oscillating its connected shaft, land particularly ltlievalbove.-V parts concerned with the functioning. of the mentioned racevvay` Toward this. end, fa .reserrotary. hook. Since the movement of these parts Voir. is, preferably, associated directly. with. .the is relatively small, it is not vnecessary to. provide hook and forms a .unitary yassembly `.wi-thithelat.- 35 aconstant supply .of lubricant lto the relatively ter, The reservoir is yof substantial capacity. so. sliding surfaces. It is suiicient to supply lubrithat it requires .lling only at infrequent inter.- cant .theretoperiodically and-.thisfis accomplished vals, i. e., not more than two or three. timesaday bythe .present invention upon each lling of the When the machine is operating `more .or less con-. reservoir. The parts referred to areV arranged to tinuously. This reservoir, due to its unitary .asiE 49* be immersed in the lubricant Within the reservoir s ociation with the rotary hook, is adapted to -be wheneverthe. latter. is substantially-lled. At the readily adjusted on the frame of the` machine to same time provision is made for adequate. lubribring about the. .desired relationshpbetween .theV cation, by. the. oil from the reservoir, of the bearhook and its cooperating needle. This phase of` y ingls-for the hooklshaft. the construction is. such that a single machine,` 45@ With .the foregoing objects, features and adproduced in accordance with. .the invention, is Vantages offtlie .invention in view, an illustrative adapted for use .on .a Variety ot different .types of embodiment ofhthe same will nowvbe described in Work. The`- machine may rembody a plurality-.ofv detail vin 'conjunction .with the accompanying hooks, ,eachhaving its associated lubrication sys# drawings., inwhich: A tem and each adapted to cooperate with a'sepa- @it Fig.. l'fis a bottom plan vieu/of a portion of the rate needle. In-such a machine `the relative base ofV Aa machine 4tou/nich the invention has spacing Vof the hooks and the needles may :be been applied, a partA of one oi?A the oil reservoirs varied, as desired, to suit any particiantypeof beingpartly broken away to disclose the interior. Work to be. performed. Thus,V the-machine ad- .Figi 2 is` a top plan view, on a somewhat enmits of'large scale,production;v larged scale, ofthe same lportion of the base ci the machine, certain cover plates being removed to disclose the mechanism more clearly.

Fig. 3 is a transverse, vertical, section across the base portion of the machine, taken along the line 3-3 of Fig. 1 through the axis of one of the Vertical hook units.

Fig. 4" is a verticahsectional view, along'gth line 4 4 of Fig. 6, through theairisofone I of the vertical hook units.

Fig. 5 is a vertical, sectional view through the hook unit, taken along the broken line 5-5 of Fig. 6. v

Fig. 6 is a horizontal, sectional view taken beneath the rotary hook in Figure 4, with a cover plate for the lubricant reservoir removed.

Fig. '1 is a perspective view of one of the roset screw 22 to a hollow, vertically extending shaft 23 at the upper end of which a rotary hook, designated generally as 24, is secured. Since the two hook units, each including a shaft 23 and its associated hook 24, are substantially identical, except for the fact that certain parts of o'rie arejof righthand construction while those` of the other are of lefthand construction, only one unit will be described in detail.

The relative sizes of the gears 20 and 2I is such thatA the hook shaft 23 will be rotated at tary hooks with its connected shaft, the latter.

being broken away in part. y y Fig. 8 is a perspective view of a core pin provided within the hollow shaft of the rotary hook. Fig. 9 is an exploded, perspective view of the several parts of the rotary hook shown in Fig. 7. Fig. 10 is a top plan view of the rotary hook with portions broken away to disclose certai details, and if 1 Fig. 11 is an exploded, perspective viewshowing, in detail, certain devices cooperating with the rotary hook. For purposes of illustration, the inventionhas been disclosed as applied to a machine of the type more fully set forth in the application of Oscar Quist, Ser. No. 326,828, led March 30, 1940, now matured into Patent No. 2,329,484, dated Sept. 14, 1943.V As disclosed in saidprior application, the machine comprises a vertical standard rising from one end of a base portion 9 and having at its upper end a laterally extending arm which overhangs the base portion.. In this overhanging arm, suitable devices are provided ior supporting and operating a needle bar carrying at its lower end a plurality of:verti. cally reciprocable needles I0, indicated in cross section in Figure 2. A shaft supported by the standard is provided with a combined pulleyand hand wheel through which power is supplied to the various operating devices .in the machine.

Within the base portion of the machine there is provided an oscillatable shaftv II (Fig. 1) supported by bearings I2 and. having securedth'ereto an arm I3 having attached to its upper end a feed dog bar i4 adapted to carry a feed dogv I5 (Fig. 2). For further details as to themeans for oscillating the shaft I I, and as to the mounting and operation of the feed dog I5, reference may be had to said Quist application. It will -be understood that portions of the feeddog are arranged to pass upwardly through, and longitudinally of, slots I6 formed in a plate I1 forming part of the work supporting surface of the ma.--

chine.

Also extending longitudinally of the base portion of the machine and suitably journaled in bearings carried by the frame is a rotatable shaft I8. This shaft is connected with the pulley wheel, hereinbefore mentioned, throughgearing of the type disclosed in said Quist application, so as to rotate in .unisonwith the main drive shaft inthe overhanging armwhich operates the needle bar. An eccentric carried bythe shaft I8 cooperating with a strap- I9 (Figi 1) serves to impart the desired lifting and lowering movements to the feed dog, as explained in the Quist application. A pair of spiral gears 28 secured tothe shaft I8 meshesfwith cooperating Y spiral gears 2l, each of whichisv secured byqa y `twice the v angular speed of the shaft I8 and, just y hence, will make two revolutions for each stitch 4formingl cycle of themachine. Shaft 23 is journaledfin1s`uitable bushings 25 and 26 mounted in spaced Vportions of a block or frame 21 constituting the main support for the rotary hook and the associated devices. The spiral gear 2l issecured to the shaft 23 between the bushings 25 and 26 within a recess 28 formed between the spaced portions of the frame 21. Frame 21 is adjustably'carried by the base portion 9 of the machine and for this purpose is provided with a split collar extension 29 adapted to surround a bushing 30 (extending through and projecting laterallyfrom one of the bearing supports 3| for the shaft I8. A clamping screw 32 cooperating with lugs formed on the split collar 29 may be turned 'to either clamp or release the frame wthrespect Ato the bushing 30. At its opposite end -the Vframey 21 is provided with an extension 33 having a rounded upper surface 34 adapted to cooperate with a at face on a portion 35 of the base 9. A screw (It passing through an elongated: slot l31 inthe extension 33 has screwthreaded.v engagement with the portion 35 of the basaand, when tightened, serves to clamp this end ofthe frame.21 in place. It will be seen from the` foregoing that the frame 21. is capable offadjustment along the bushing 30 and portion 35of1ithe'b`ase; by simply loosening the screws 32 and 38 and lit may be clamped in any desired position Vby tightening these screws. At the sametimethe-spi'ral gear 2|] may be shifted along the-shaft vI8 by loosening the retaining screw 38, thusmaintaining the proper relationship between the `gears 2|] and 2l. As best seen in Figure l, all of the clamping screws, 32, V36 and 38, arereadily 'accessible from the under side of the base.. The; adjustment ofy the parts in the manner explained, as 'will be understood, is to enable thezs'ame mechanisnrto be accommodated to machinesfin'which different spacings may be desiredbetweenlthe lines of stitching formed by the VIneedles and 4rotary hooks. Thus, the machine 'lends itself to large scale production since varied requirements may be met by the interchangeable useof `a relatively small number of parts and bythe proper adjustment of the parts described..

Between the clamping portions 23 and 33 of the frame2-1 and laterally inline with the shaft 23, there fis.- provided an enlarged lubricant reservoir 39l (Figfi). .This .reservoir is closed at its end by a plate A4l) and'a gasket 4I secured by screws 42. At itstop is 1an Vinlet .opening 43, this preferably havingfin'sertedtherein a cup44 adapted to be closed; in a well known manner, by a spring cap; The upper end of the reservoir i-s provided with an'extension 45 which surroundsA the shaft 23. This not only increases the capacity of the reservoir but :alsoprovides aj chamber in which certain operating devices=;arehoused and subjected to occasional lubrication. The top of theextension or chamber 45 is substantially closed by a plate 46, shown in detail in Fig. 11, secured byfscrews or the like. v

At the lower end of the reservoir 39 is .provided la tube 41, one end of vwhich extends through the wall of the reservoir, beneath the 'closure plate 40, and the other end 41a of which extends into an opening 48 .through the opposite wall of 'the reservoir communicating with a small chamber 49 surrounding the lower endof the shaft 23. A needle valve 56, having its tapered, pointed end 50a extending into apassage 41bin the'end l41a of the tube, is adapted to regulate accuratelyithe size ofthe inlet to the passage 41h throughwhich the lubricant may flow. Adjacent its outer 'end the needle valve is provided wi-tha .screwthreaded portion 56h cooperating with asimilarly threaded portion of the tube-41 so that the de-4 sired adjustment of the valve maybe effected. A plurality of small openings 41o admits theilubricant from the reservoir 39 to the interior of the tube 41 and allows it to flow through therestricted passage around the point 50a. of the needle valve.

The lower end of the small chamber v49 is closed by a screw cap l provided with a gasket -52 to form an effective seal. Removal of this cap allows complete drainlage of the oil from thereservoir. Cap 5| is in axial alinement with the shaft 23 and is provided with a diametrically extending slot 5|a adapted to receive a tongue 53 at the lower end of a core pin 54. This core pin has a slight clearance from the .inner wall of the hollow shaft 23 and is provided with a spira] groove 55 (Fig. 8) throughout the major portion of its length. As indicated, however, the groove is preferably terminated a slight .distance up from the lower end of the pin and does not extend below the lower end of the shaft 23. The pin 54 is retained by the cap 5I and is held stationary by the cooperation of tongue 53 with the groove 51a. `During the rotation of the shaft :23, the stationary, spiral groove 55 cooperating with the cylindrical inner surface of the hollow shaft will cause such oil as is delivered to the lower end of the shaft to be forced upwardly into a small chamber 56 formed lat the top of .theho-llow shaft and from which extends a small tube 51 communicating with the raceway-58 to be lubricated. This raceway, as will be understood, is formed in part in the inner wall of the rotating outer element of the hook land in lpart between a shoulder 59 (Fig. 9) on this kelementand the under surface of a removable p1ate60 which, when removed permits the introduction and removal of the inner element or stationary bobbin case 6|. Ribs 62 provided on the outer surfaceof this bobbin case cooperate with the raceway and it is this coaction which necessitates the lubrication provided by the present invention. The bobbin 63 which supplies the under thread in the stitchforming operation is retained within the rbobibin case in a well known manner.

At the upper end of `the shaft 23, just beneath the rotating hook element, the shaft is provided with an eccentric portion 64 which extends through an opening 65 in the cover plate 46. Beneath the cover plate there is mounted on the eccentric a strap portion of a pitman 66 having an opening 61 at its free end adapted to lbe engaged over the head of a screw 68 carried by an arm 69 of a rock member. At the opposite end of the arm 68 there is formed an integral sleeve I0 adapted to nt over a reduced portion 'Il at the upper end of a pin 12 inserted in a hole in the frame or block 21 and, held therein by a screw 13 (Fig). v The-'sleeve is retainedfon'the'pin'by a large-'Sheadedfscrew I14 cooperating with internal threads in the upper end of the pin. Integral with the upper end ofthe sleeve 10 a latenally extending arm15 isprovided which carries atits free end arblockl-having a groove adapted to receive the shank of a member 11., This member is retained in the vgroove of the block-16 by means of a screw 18 (Fig. 5) which cooperates with an elongated slot "19 Vin the member to `permit ad- Jus'tment of the latter. The free end of the member 11 is arranged to cooperatewithan upwardly inclinedfportion 8`0 of the bobbin case -6| tol-enable temporary disengagement of a projection 8| on vthe'bobbin case from la cooperating retaining notch so lthat the needle thread loop, which has previouslybeen-passed around the bobbin case, may be completelyreleased anddrawnupwardly against the under side of the work. The cover plate 46 is cut out at one edge, as indicated at 82, in the region ofthe sleeve 10.

The operation of the improved construction is believed to be'clear from the foregoing. However, a brief rsum will now be given. Periodically in the use of the machine, oil will be introduced into the-reservoir -39 associa'tedwith each of the lrotary hook units. vThisis accomplished through the'cups44. Upon each filling, the 1ubric'ant -is preferably carried sub-stantially'to the top of the lling cup so that it temporarily submerges at least a portion of the eccentric 64 and the relatively moving surfaces ofthe parts-operated by vthis eccentric. From the reservoir 39 the'lubricant will pass through'the openings-'41C into the tube 41 and lfrom the latter aroundlthe needle valve and through vpassage -41b into the passage 48 and chamber 49. Assuming themachine to be at rest,the lubricant willseek a level within-the `hollow shaftl23 substantially the-same as that in the reservoir. Now, as the-machine is operated and the .shaft23isrotated through the spiral gears 26 and 2l, theoil within the'shaft is forced by the-action ofthe grooved core pininto the small chamber 56 andthroughthe tube V51 to the raceway. As the lubricant-is thus forced from the interior of the 'shafty more vlubricant is supplied to the shaft from the reservoir through the channels explained but it ilowscnly at the rate permitted by the needle valve 50. This-may readily be regulated to insure the delivery to the interior of :the shaft Aof .just sufficient lubricant-to meet the requirements of the raceway. The wastage of excess lubricant is 'thus avoided and soalso the soiling ofthe workand the threads is avoided. Whenever the reservoir is filled-a. certain amount of the lubricantwill iind its way into the-bearing bushing 25 and even when the reservoir is only partly filled some of the lubricant will nd its way into thebushing 26. Adequate lubrication of the shaft 23 is thus provided.

While an illustrative embodiment of the invention has been described in considerable detail, it will be understood that numerous variations may be made in the construction and arrangement of' the parts and in the mode of operation ofthe system without departing from the general principles and scope of the invention. The terms and expressions used herein have been used as terms` of description and not of limitation.

What I claim is: f

1. In a sewing machine a loop-taking unit, comprising a frame, bearings mounted in said frame in vertical alinement, a rotary hook of the raceway type having its axis disposed substantially vertically, a shaft rigidly connected with said hook and journalled in said bearings, said shaft having a longitudinal passage therein, av gear ,on said shaft between said bearings for rotating the shaft, an oil supply reservoir carried by said frame, a passage in said frame connecting said reservoir with said passage in the shaft for .the delivery of oil thereto by gravity, a valve cooperating with said passage in the frame and adjustable exteriorly thereof lfor regulating the flow of oil to said passage in the-shaft, said valve permitting delivery of oil to the passagein the shaft at a rate sufficient only tl meet the lubrication requirements of said raceway, but being adjustable to either completely close off said passage or allow the flow of excess lubricant therethrough to flush out accumulated dirt, and stationary means carried by said frame cooperating with the i" shaftl upon rotation thereof to cause delivery of the oil from the passage in the shaft by a positive pumping action to the raceway of said rotary hook,

2. In a sewing machine, stitch-forming devices including a rotary hook of the raceway type, a driving shaft connected with said hook, a block in which said shaft is journalled, means for rotating said shaft, a lubricant supply reservoir in said block, a passage extending longitudinally of said shaft and communicating at one end with said reservoir to receive lubricant by gravity therefrom and at the other end with the raceway 0f said hook, a perforated tube extending through said reservoir adjacent its bottom and arranged to deliver lubricant to said passage in the shaft, a valve extending into said tube and accessible exteriorly of said reservoir for adjustment to regulate the rate of delivery of lubricant from said reservoir to said passage, and means operable upon rotation of said shaft for acting upon the lubricant delivered to the passage therein and lifting the lubricant within said passage and causing it to be delivered by a positive pumping action to said raceway. Y

3. In a sewing machine, stitch-forming devices including a vertical axis rotary hook of the raceway type, a vertically disposed driving shaft connected with said hook, means for rotating said shaft, a lubricant supply reservoir, a passage eX- tending longitudinally of said shaft and communicating at one end with said reservoir to receive lubricant by gravity therefrom and at the other end with the raceway of said hook, means between said reservoir and said passage for accurately regulating the delivery of lubricant'to said passage in accordance with the lubrication requirements of the raceway,` and means within the shaft and operable upon rotation of said shaft for lifting the lubricant delivered to said passage and causing it to be delivered by posi- .tive pumping' action to said raceway, said last recited means comprising a, spirally grooved core pin having the groove therein terminating within the shaft above the lower end of said passage, the portion of said core pin below the lower'end of said groove having a relatively close fit within said passage.

. 4. In a sewing machine a loop-taking unit comprising. a frame, a vertically disposed shaft journalled in' said frame and having a longitudinally extending passage therein, a rotary hook secured to the upper end of said shaft, said hook having a raceway, a lubricant supply reservoir carried by said Vframe, said reservoir extending from substantitally the level of the lower end of said shaft upwardly to a point substantially in line with the underside of said hook, means including a perforated tube serving to connect said reservoir with said passage in vthe shaft for delivering lubricant thereto by gravity from said reservoir,

' valve means extending into said tube and adjustable exteriorly of said frame for accurately regulating the amount of lubricant delivered to said passage in accordance with the lubricant requirements of the raceway, said adjustable means being adapted to readily enable delivery of excess lubricant to said passage for the purpose of flushing out accumulated dirt, and a plurality of impelling means operable in series upon rotation cf saidshaft for delivering the lubricant from the passage therein by positive pumping action to said raceway.

GEORGE SAUER REFERENCES CITED The following references are of record in the file of this patent:

p UNITED STATES PATENTS Number Name Date 1,311,817 Hohmann July 29, 1919 1,936,372 Waterman Nov. 21, 1933 2,089,167 Smith Aug. 3, 1937 2,112,172 Mackay Mar. 22, 1938 2,248,508 Myers July 8, 1941 2,283,869 Graesser May 19, 1942 2,095,450 Myers Oct. 12, 1937 2,128,573 Myers Aug, 30, 1938 914,794 Coe Mar. v9, 1909 1,452,180 Brunner Apr. 17, 1923 1,604,078 Schneider Oct. 19, 1926 1,679,199 Baker July 31, 1928 1,544,266 Mueller et al June 30, 1925 2,334,644 Parry Nov. 16, 1943 2,304,741 Myers Dec. 8, 1942 27,370,930 Batting Mar. 6, 1945 

